Hoist Capacity Chart Conditions and Lookup
- Identify every condition underlying the chart capacities.
- Match hoist model, body length, overhang, and dump angle.
- Distinguish chart guidance from installation and adjustment instructions.
- Tape measure — Check body length, overhang, and hinge-pivot-to-floor separation using the applicable reference points; do not guess unclear measurement endpoints.
- Spirit level — Help establish a level reference when checking vertical separation.
- Digital angle gauge — Help verify body angle when safe access and an approved operating procedure are available; do not raise the body solely on the authority of the capacity chart.
- Flashlight — Read hoist identification and inspect accessible hinge and floor reference points.
The hoist document presents its capacities as general guidance because applications vary. Its stated basis is a water-level, non-diminishing load, at least 3 inches of vertical separation between the rear hinge pivot and trailer floor, and hydraulic relief pressure of 3,200 psi. These are chart assumptions, not a supplied hydraulic adjustment procedure.
Select the exact hoist model, then match column A body length in feet and column B overhang in inches. Read capacity in tons from the appropriate 45° or 50° column. For PH310 with an 8-foot body and 24-inch overhang, the listed capacities are 5.5 tons at 45° and 4.9 tons at 50°.
Page 2 separates PH416 from PH516 even where dimensions match. At a 12-foot body and 18-inch overhang, PH416 is listed at 8.3 tons for 45° and 7.5 tons for 50°. PH516 at the same dimensions is listed at 8.6 and 7.8 tons respectively.
Page 3 similarly separates PH520 from PH616-5. With a 14-foot body and 18-inch overhang, PH520 is listed at 9.3 tons at 45° and 8.5 tons at 50°, while PH616-5 is listed at 7.9 and 7.1 tons. These examples show why dimensions alone are insufficient: the model and dump-angle column must also match.
How It Works
Conditional capacity, not an operating authorization
The chart provides general guidance based on a water-level, non-diminishing load, at least 3 inches of vertical separation between the rear hinge pivot and trailer floor, and hydraulic relief pressure of 3,200 psi. Load distribution changes the turning effect about the hinge, so an application that differs from the stated assumptions cannot automatically inherit the listed capacity. The pressure value is a chart basis, not permission or a procedure to adjust the hydraulic system.
Follow the complete lookup path
Select the exact hoist model, match column A body length in feet and column B overhang in inches, then read capacity in tons under the applicable 45° or 50° column. For PH310 with an 8-foot body and 24-inch overhang, the chart lists 5.5 tons at 45° and 4.9 tons at 50°. Hoist leverage changes with geometry and body position, which is why the angle column is part of the capacity selection rather than an optional detail.
Matching dimensions do not make models interchangeable
With a 14-foot body and 18-inch overhang, PH520 is listed at 9.3 tons at 45° and 8.5 tons at 50°, while PH616-5 is listed at 7.9 tons at 45° and 7.1 tons at 50°. These different capacities demonstrate that body dimensions alone cannot establish the correct rating. Keep the model identification and dump-angle selection attached to the capacity whenever recording or communicating a lookup.
Step-by-Step Procedure
0/6 doneChart Basis and Selected Capacities
| Minimum rear hinge pivot to floor vertical height | 3 inches |
| Hydraulic relief-pressure basis | 3,200 psi |
| PH310, 8-foot body, 24-inch overhang | 5.5 tons at 45°; 4.9 tons at 50° |
| PH416, 12-foot body, 18-inch overhang | 8.3 tons at 45°; 7.5 tons at 50° |
| PH516, 12-foot body, 18-inch overhang | 8.6 tons at 45°; 7.8 tons at 50° |
| PH520, 14-foot body, 18-inch overhang | 9.3 tons at 45°; 8.5 tons at 50° |
| PH616-5, 14-foot body, 18-inch overhang | 7.9 tons at 45°; 7.1 tons at 50° |
Diagnostic Chart
| Symptom | Check | Spec / Expected | Likely cause & fix |
|---|---|---|---|
| Different technicians obtain different capacities for matching body dimensions. | Compare the actual hoist identification with the model table each technician selected, then compare the angle columns. | At a 12-foot body and 18-inch overhang, PH416 is listed at 8.3 tons at 45° and 7.5 tons at 50°; PH516 is listed at 8.6 tons at 45° and 7.8 tons at 50°. | A neighboring model table or a different dump-angle column was used. Basis: Bostail Power Hoist Capacity Chart |
| A PH310 capacity entry does not agree with the intended dump angle. | Confirm the body-length and overhang row, then trace directly to the applicable angle heading. | PH310, 8-foot body, 24-inch overhang: 5.5 tons at 45°; 4.9 tons at 50°. | The capacity was copied from the wrong angle column or recorded without its angle condition. Basis: Bostail Power Hoist Capacity Chart |
| The row matches, but applicability to the trailer remains uncertain. | Review the load assumption and verify the hinge-pivot-to-floor vertical separation. Establish whether the documented hydraulic configuration matches the chart basis without treating the chart as an adjustment procedure. | Water-level, non-diminishing load; at least 3 inches of vertical separation; hydraulic relief-pressure basis of 3,200 psi. | A chart assumption is unverified or differs from the application. Basis: Bostail Power Hoist Capacity Chart |
| The hoist struggles despite a load believed to be within the chart capacity. | Stop the lift and follow the equipment manufacturer's safe diagnostic procedure. Check for mechanical binding and hydraulic faults without entering beneath an unsupported body or increasing relief pressure to force movement. | The capacity lookup alone does not establish hydraulic or mechanical serviceability. | Mechanical resistance or a hydraulic fault may prevent an otherwise correctly identified hoist from performing as expected. Basis: General shop practice |
At the Bay: Diagnose the Case
CASE 1 / 4
Different technicians obtain different capacities for matching body dimensions.
- Test
- Compare
- Correct
Select the next check
Basis: Bostail Power Hoist Capacity Chart. A likely cause is a hypothesis; confirm it with the applicable service procedure before repair.
Common Bay Mistakes
- ✕ Selecting a model table by matching dimensions alone.
- ✕ Quoting capacity without its dump-angle condition.
- ✕ Assuming the load will diminish instead of retaining the chart assumption.
- ✕ Using the relief-pressure basis as an adjustment instruction.
Quick Check
Practice only — not scored.
Plan the Service Sequence
Planning practice only. Follow the applicable manufacturer's instructions, employer safety program and qualified supervision on real equipment.
Plan the first action. Compare the service steps with the bay mistakes.
Hands-on: Shop Test Equipment
Dial Indicator — Bearing End Play
Magnetic-base dial indicator (0.001 in) on the hub face, spindle nut adjustment
🛠 Equip your bay for this test →Symptom: Bearing service — set end play after repack.
Spec limits used
- 0.001–0.010 in — Allowable end play, double-nut wheel end (Dexter 9-15K service manual, p.64)
- 0.008 in — Nev-R-Lube 50 mm max axial end play (Dexter 059-831-00)
- illustrative only — Face runout limit (General shop practice)
Simulated readings for practice. Always follow the manufacturer's procedure and values on a real trailer.
Source: Bostail Power Hoist Capacity Chart — 1-3